Dr. Stacy Loeb is an urologist with significant experience in clinical care and research on prostate cancer. This K07 award will allow the applicant to gain additional skills to foster a career as an independent investigator. This will be accomplished in collaboration with a multidisciplinary mentorship team. Background: One in 6 US men are diagnosed with prostate cancer during their lifetime but only 1 in 36 die from it. Treatment is often curative but may lead to side effects. An alternative option is conservative management, which delays or avoids the side effects of treatment. The major risk of conservative management is that the disease may progress without treatment. During conservative management, there are many options for follow-up testing to monitor for disease progression, ranging from blood tests and physical exams to imaging and biopsies. However, there is no consensus regarding the type, frequency and sequence of follow-up testing. More frequent and invasive tests may identify disease progression earlier, but may increase costs and complications. In a recent Consensus Conference, the NIH declared that identifying the optimal protocol for conservative management is a major priority in prostate cancer research. Project: The goal of this proposal is to compare the effectiveness, harms and costs of alternative strategies for conservative management using a mathematical model. The model will also look at the influence of patient features, tumor features, and preferences on the choice of strategy. This information will be distributed to prostate cancer patients and physicians through the preliminary design of a website. The research plan coincides with the applicant's proposed training curriculum, to ensure a successful bridge to submission of an R01 proposal. Mastery of these new skills will help the applicant transition into an independent cancer investigator with the capacity to compare the effectiveness and costs of new prostate cancer management options, and to design decision support tools for prostate cancer patients.